Valve seat refacing tool



Jan. 15, 1935. Q L. 0. BEARD 1,988,411

VALVE SEAT REFACING TOOL Filed Jan. 16, 195:5

INVENTOR' ATTORNEY.

Patented Jan. 15, 1935 VALVE SEAT REFACING TOOL Lawrence 0. Beard, Lancaster, Pa;

Application January 16 2 Claims.

This invention relates to improvements in valve seat refacing tools, and has more particular reference to an improvement for refacing the Worn or imperfect valve seats of an internal combustion engine.

An object of the invention is to provide simple and effective means for clamping the cutter bladesto the cutter head whereby danger of breaking the relatively hard blades which must be employed is reduced to a minimum.

Another object of the invention is to provide a valve seat refacing tool adaptable for use with various standard makes of pilots.

Other advantages will be apparent as the specification is read in connection with the accompanying drawing, in which:

Figure 1 is a perspective View of the tool partly in section;

Figure 2 is a bottomplan of the tool shown in Figure 1;

Figure 3 shows the various parts of the tool disassembled; and

Figure 4 is an enlarged detail partly in section and partly broken away showing the taper of the bushing and handle member.

Referring more specifically to the drawing 1 denotes a preferably cast iron cutter head of substantially inverted cone shape and having flat upper and lower faces 2 and 3 respectively. Narrow ring like portion 4 extends between the top of conical face 5 of the cutter head to the upper flat surface 2 thereof, just referred to. The cutter head is formed with a plurality of open ended slots 6 adapted to snugly but slidably receive therein the cutter blades 7. These slots;

rectangular cross section except at their ends.- Thus the lower end of each blade is formed with 10. The length of blades 7 is such that when' inserted in the slots 6 the upper angular end or face 10 of the blades will be substantially bisected by a peripheral line drawn approximately midway the top and bottom extremities of the ring like portion 4 of the cutter head, and the respective lower end faces 8 and 9 will be flush 1933, Serial No. 652,055

with the flat surface 3 of the cutter head and the wall of bore ll extending axially through said cutter head.

A top plate or cap 12 of relatively stiff sheet steel seating upon the top surface 2 of the cutter head is formed with a depending peripheral flange 13 which snugly engages the peripheral ring like portion 4. The lower edge of this flange terminates approximately mid-way the depth or top and bottom extremities of ring like portion 4 and engages the angular upper ends 10 of the blades 7 midway the top and bottom edges thereof, thus securely and nonresiliently clamping the blades in place.

The cap 12 is provided with a central opening screwed home upon the extended threadedend of the bushing and against the top of the cap,

the flange 13 of the cap engages the upper end face 10, and collar 16 of the bushing engages the lower end faces 8 of the blades 7, thus clamping the blades tightly in place. The bushing 15 has a straight exterior adapted to snugly fit the straight bore or opening 11 through the cutter head, and the interior of the bushing is slightly tapered, as best illustrated'in Figure 4,

that is the diameter of the bore of the bushing is gradually reduced from the top to the bottom thereof; I

, The tool is operated by means of a cylindrical shank or handle member 18 slightly tapered at its lower end to fit within the oppositely tapered bore of bushing. or sleeve 15. The upper end of handle member 18 is formed with wrench engaging faces 19 and a hand grip20, while its lower end is formed with a threaded bore 21 to receive the reduced threaded end 22 of a pilot stem 23. In use the tool is rotated either by means of thehand grip 20, or by applying a standard'wrench to the squared end 19 of the handle member. If desired the pilot stem and the handle member may be made integral.

When the handle member 18 is pushed homein the bushing 15, the former becomes tightly wedged in place, and the downward pressure exerted in grinding operations prevents relative turning of these parts.

' Having thus described my invention, What I claim is:

1. A valve seat refacing head adapted to be interchangeably connected with a handle and opposite the outer face of said, plate, said 'plate having its flanged portion engaged with the upper ends of said cutter blades, and. said ring nut being adapted to draw the flanged end of said bushing and said plate toward each other and clamping the blades in proper-alignment in said cutter head. 7

2. A valve seat refacing head as described in claim 1, wherein the externally threaded bushing is internally tapered.

r LAWRENCE O. BEARD. 

